Brake drum



July-23, 1935. P. E. BAKER Er Al.

BRAKE DRUM Original Filed June 13, 1952 v.IN1/Eweka: Paul Eid/fer' ggd/Paal W'aerwsle; ATTORNEY.

Patented July 23, 1935 i f y UNITED sTATEs PATENT OFFICE BRAKE DRUM Paul E. Baker and Paul W. Gaenssle, Detroit,

Mich., assignors to Budd Wheel Company, Philadelphia, Pa., a corporation of Pennsylvania Application June 13, 1932, serial No. 616,824 Renewed June 4, 1935 7 Claims. (Cl. 18S-218) The invention relates to vehicle brake drums width and extend across the axially extending and particularly to the cooling ofl such brake portion i4 of the drum in angularly spaced redrums in order to obtain therefrom the maximum lationship with respect to the radially extending eflciency in use. I y ribs I3 in the mounting plate II. The radially 5 'I'he prime object of our invention is to adeextending passages 20 are arranged in series 5 quately cool vehicle brake drums in such a manaxially and radially adjacent the continuous cirner as to increase their eiiiciency and to effect Cumferental passages I3. These radially extendthis cooling in the simplest manner possible. ing passages 20 open outwardly to the exterior Other objects relate to improved detail, and the surface of the outer portion I6.

provision of a removable braking portion. The ribs I3 and mounting plate II, and the l0 Broadly, we have achieved the objects of our axiallyr extending passages I9 are so arranged in invention by providing passages within the brakradial alignment that a CentinuOuS Passage 0f ing portion of the brake drum, whereby air mayA air iS OrCed OutWardly 0f the mOunting plate and be circulated through. the drum in order to cool aCrOSS the aXially extending pertiOn I4 0f the the same. We have also provided novel means for drum. It will be seen that the ribs I3 in the l5 the demountable securement of a braking memmounting plate Il tend to act as venes, stirring ber. up the air within the drum, and inducing a cen- Other objects and advantages will be apparent trifugal flOW 0f air outwardly toward the braking in the reading of. the sub-joined specifications in Dertien l5. ThiS Centrifugal fiOW 0f air iS earlight of the attached drawing, in which ried axially into the braking Dertien I5 by PaS- 20 Figure 1 is a partial elevational view of a brake Sages I9 This lOW 0f air iS augmented by a eirdrum embodying our invention cumferential ow passing through passages I8,

Figure 2 is a cross sectional view taken on line in and Out 0f the radial DaSSageS 20. 2-2 of Figure 1 By such provision for air circulation entirely Figure 3 is a cross sectional view taken on line Surrounding the braking Dertien I5, yWe have ade- 25 3 3 of Figure 1. quately cooled this portion, thus avoiding the Fig. 4 is a cross sectional view through a modi- Serious Consequences of over-heating, which confled form of our invention, taken on a line cor- Sequence usually takes the ferm 0f bell meu-thing, responding to line 2-2 of Figure 1. irregular expansion and uneven wear. We have Figure 5 is a View of the device of. Figure 4, increased the service life of the brake drum many 30 taken on a line corresponding to iine 3 3 of Figtimes by such provision. It will be appreciated ure 1, that the circulation of air throughout the various Referring now to the drawing by reference passages indieated generally by numeral `I`I characters, drum I0 consists of a'radially extend- Causes the heat generated by repeated braking ing mounting plate I I having an annular series actions to be conveyed away from the braking u of equally spaced securing holes I2 through which portion I5 and into the open air. the drum, as a whole, is adapted to be secured In the modification ShOWn in Figures 4 and 5, to the usual wheel hub, not shown. 'I'he inner we have provided a removable braking portion 2|, axial face of the mounting plate Il is provided having radially extending marginal anges 22 40 with a. series of radially extending ribs I3 exand 23, through the outer flange 22 of which the 4. tending over substantially the entire surface of removable portion 2l is secured by means of an the mounting plate. Drum I0 is further provided annular series of axially extending studs 24 to With en axially extending Dertien indicated bosses 25- on the axially extending portion I4 of generally by numeral -Ilgconsisting of. a braking the drum m. The inner surface 25 of the' ax- Portion l5 0f Cylmdrlcal Contour and an Outer ially extending portion I4 is provided with ribbed surface portion I6 also of cylindrical contour f ormat1ons, the spaces between which are very Referring particularly to Figures 2 and 3, which much the sa e as those desc .bed in connection Show a' cast brake drum We have provided be' with Figures 1, 2 and 3, embodying axially, radih brakin orti n I5 tween t e g p o and the outer sur ally, and circumferentially extending passages,

50 lace portion I6, a series Aof cored slots or passages n extending axially, radially and circum through which air circulates to cool the drum.

ferentially of the drum. We have preferred to BY Providing a removable braking Portion We are make the circumferential passages la continuous able to eieot a replacement of this portion at as shown clearly in the respective gures. The such time that excessive wear has taken place.

56 axially extending passages I9 are of suitable and by providing ribbed portions in the inner surface 26 of the axially extending portion Il, we obtain the desired passages for the circulation of air, as well as supports for the removable portion 2|.

It will be seen that the objects of our invention are achieved in the manner characterized by simplicity and general utility. The cored passages in the respective castings shown afford am-.

ple provision for the passage and circulation of air therethrough, insuring adequate cooling of the drum as a, whole, and lengthening the service life of the drum. By a simple arrangement we have been able to make the braking portion removable, in conjunction with a ribbed securing member, the assembly of which members incorporates the same system of air passages' as does the unitary drum. It will be understood that while the invention is particularly applicable to cast brake drums, it is entirely possible that the cored passages therein might be formed in other types of drums.

tinuous passages, a plurality of axially extending passages therein, said last-named passages being in continuation of continuous slotted portions in said mounting portion and radially extending passages interconnecting intersecting areas of said axial and annular passages at the outer surface ofsaid braking portion. v

2. A brake drum comprising, in combination, a mounting portion, a braking portion, passages .Within said braking portion, and ribs in said mounting portion adapted to circulate air through said passages to cool the drum.

3. A brake drum having an axially extending passage, a radially' extending passage and a passage extending circuxnferentially a substantial distance within the braking portion thereof.

4. A brake comprising a perforate outer cylinder, an imperforate braking cylinder spaced radially inwardly thereof, means interbracing and supporting the cylinders each to each and shaped to provide symmetrical axial and peripheral passages between the cylinders, and a drum head having radial vanes for directing air to the passages between the cylinders.

5. A brake comprising a braking cylinder having radially outwardly and inwardly projecting flanges at its respective ends, and a mounting member including a cylinder and an integral drum head at one end of its cylinder, the mounting member cylinder having radial side openings and being nested over the braking cylinder in spaced relation thereto with its drum head in adjacent axially-spaced relation to the end of the braking cylinder having the inward ilange, the mounting member cylinder also having portions seating it on said outwardly extending ilange and spacing it from the braking cylinder to therewith form axial and peripheral passages between the cylinders, and the drum head having a radially inner mounting portion and forming radial passages communicating with the passages between the cylinders.

6. A brake comprising a cast metal unit having all of its parts 'homogeneously integrally united to each other and comprising a braking cylinder having cored axial and peripheral passages between its inner and outer cylindrical surfaces and cored radial passages in its outer surface communicating with said rst passages, the unit also including a drum head homogeneously integral with the cylinder having a radially inner mounting portion and radial passages directed toward, and communicating with, the cylinder passages.

7. A brake including a spaced wall cylinder de- PAUL E. BAKER. PAUL 'W. GAENSSLE. 

